In 1969, when Renee Weisman started working at IBM in Poughkeepsie, N.Y., she says it wasn't unusual for a man to approach her desk and ask her to type up a letter.

"I'm not a secretary," she'd say. "I'm an engineer."

At the time, Weisman was the lone woman engineer among 400 in her division. She says the men were often shocked to hear her job title. "It was very unusual for them," she recalls. "But I didn't think a lot about being a woman. I focused on the job I had to do."

In the span of nearly four decades, Weisman ascended the ranks at the technology giant, occupying varying leadership and management titles -- including distinguished engineer and director of engineering -- before her retirement in 2007.

Achieving success in a male-dominated profession often required her to defy gender stereotypes. She says she learned the importance of making sure her own work was noticed, for example -- and of voicing her opinions: "If you're not assertive, they walk all over you. Or they ignore you. You have to stand up and be heard." (She is quick to point out that any gender biases she faced came from individuals, not institutional policies).

Weisman, who is now 63 and a Poughkeepsie-based writer, teacher and consultant focusing on gender dynamics in the workplace, says this kind of assertive behavior still doesn't come easily to many professional women.

It can also have a "backlash" effect: Research has shown that women who display stereotypically masculine behaviors associated with successful leadership (such as aggressiveness and assertiveness) are often judged negatively -- and held back professionally -- for not behaving in a feminine way.

But a recent study by Mandy O'Neill, an assistant professor of management at the George Mason University School of Management and Charles O'Reilly, a professor at Stanford's Graduate School of Business, suggests a possible strategy for navigating this paradox. Women who display masculine behaviors such as self-confidence, assertiveness and dominance -- but who can self-monitor, or modulate these behaviors depending on the situation -- receive more promotions than their peers, according to O'Neill's and O'Reilly's study.

The researchers define self-monitoring as "individuals' ability to accurately assess social situations and to project situationally appropriate responses." (Here is an 18-item questionnaire you can use to find out whether you're a high or low self-monitor.)

O'Neill and O'Reilly looked at students of an MBA program seven and eight years after their graduation, and found that masculine women who were high self-monitors received three times as many promotions as masculine women who were low self-monitors. The high-self-monitoring masculine women also received more promotions than both masculine and feminine men, regardless of the men's self-monitoring abilities.

The subjects' masculinity or femininity was measured by the types of organizational cultures they preferred (aggressive versus supportive), along with more conventional tests as well as outside observers' ratings. Their self-monitoring capabilities were assessed with a widely used scale.

O'Neill has heard criticisms that "masculine" and "feminine" categories reinforce gender stereotypes, but she points out that masculine and feminine traits can, of course, appear in either sex. And it turns out that there's a lot of consistency between the type of (masculine or feminine) work culture people prefer and the traits they display.

While O'Neill and O'Reilly point out several limitations to their study (including a small sample size and the fact that self-monitoring may be hard to distinguish from general "likeability"), O'Neill says the research runs counter to a spurious conclusion that she's seen crop up in the media: namely, that because of the backlash effect against masculine women, it's better to just "act like a lady."

"That's not what we're finding at all," she says. "But there's so much of a desire to find a place or traditional feminine values in management that people want to interpret [this research] however they can."

Instead, O'Reilly says, her work suggests that "women can really be even better than everybody else. If you're one of these women who is masculine and self-monitoring, you're more likely to be promoted."

Renee Weisman says both the backlash effect and O'Neill's and O'Reilly's findings resonate with her own decades-long experience in a male-dominated industry, where she saw overly aggressive behavior from women met with resistance from men: "They would badmouth a woman who turned it on too strongly," Weisman says, "and then typically figure out ways to not do what she wanted."

And Weisman recounts examples from her own management philosophy that sound a lot like self-monitoring. "You can't manage everybody the same way," she says. "Sometimes you have to be more assertive -- to defend an unpopular position, for example. At other times you might need to let someone else feel like they're in charge. Or if someone has done something to help you, you can acknowledge them and make them feel good about it -- using more of those nurturing, female qualities."

To a woman who's adept at turning on and off certain masculine or feminine traits depending on context, O'Neill's and O'Reilly's research may seem obvious.

But another question is whether self-monitoring can work for those who aren't already good at it. In other words, is it teachable?

O'Neill suspects it is. "There's no reason to believe that self-monitoring can't be trained," she says. We all have different base levels in terms of our ability to pay attention to the environment and adjust ourselves, O'Neill says, but she can easily envision "interventions" to help women deal with the challenge of calibrating their levels of masculine behavior in the workplace. For a precedent, she says, just look at the huge industry that's developed around emotional-intelligence training.

But do strategies to help women modulate their masculinity to best effect in a male-dominated work culture simply let that male-dominated work culture off the hook for its deeply entrenched disparities?

To be sure, business-management positions are still overwhelmingly dominated by men. A recent report from Catalyst, a non-profit organization dedicated to women's advancement in the workplace, found that in 2010, men held 82 percent of board seats in Fortune 100 companies, where women had gained only 16 board seats between 2004 and 2010, a negligible (1.1 percent) increase. Fortune 500 boards were even less diverse than Fortune 100 boards, with men holding close to 85 percent of all board seats.

Jeanine Prime, senior research director for Catalyst, says that while "both women and men today they think it's a level playing field, and many people doubt that gender biases are still entrenched, our research shows pretty good evidence that there's bias happening."

Part of the reason we still see such disparities in corporate leadership, Prime says, is that the "criteria seen as prerequisites for leadership are defined by people who already hold those positions."

Women are walking a tightrope, Prime says. "Although studies show that gender isn't really a good predictor of leadership, the idea persists in our culture that a successful manager should appear assertive, confident, aggressive -- traits we don't usually expect in women. "

It makes sense, she adds, that many woman may be "self monitoring" in order to navigate a perennial dilemma: "How do I prove that I'm a leader and still appear like a woman?"